War of the Worlds: Curiosity fires first laser shot on Mars

NASA’s Mars rover Curiosity has fired its laser for the first time. Its target wasn’t attacking Martians, but a 7 cm (2.75 inch) wide rock called “Coronation” (AKA N165) about 10 feet (3 m) from the rover. Curiosity’s laser fired 30 pulses over a ten-second interval, hitting Coronation with one million watts for five-one billionths of a second. As tiny bits of Coronation vaporized into a glowing plasma, Curiosity's ChemCam analyzed the stone’s makeup by means of a telescope and three spectrometers.
The laser shot was part of Curiosity’s three-week shakedown before starting its two-year mission to explore the Red Planet. The firing on Sunday August 19 was “target practice,” but the spectral analysis will also help scientists to determine if the laser is blasting just rock or any dust covering the stone as well. This is the first time that such a laser experiment has been conducted on another planet.

The laser is part of Curiosity’s ChemCam system. It’s a suite of instruments housed partly on top of the rover’s mast and includes a telescope, the laser and a remote micro-imager. A fiberoptic cable runs from the mast down to the three spectrometers inside the rover used to analyze the vaporized rocks. From a distance of 23 feet (7 m), ChemCam can identify rocks, determine soil compositions, measure chemical elements present, recognize the presence of ice or water molecules and even provide visual assistance for drilling operations.

ChemCam was developed mainly by the Los Alamos National Laboratory (LANL), Los Alamos, New Mexico and the Centre d'Etude Spatiale des Rayonnements (CESR), Toulouse, France.

On the move

dramatic landing maneuver, is also preparing to move under its own power for the first time. The first movements will be fairly modest, involving only turning the rover’s wheels from side to side. Then Curiosity will roll one rover-length, which is about 10 feet (3 m), turn 90 degrees, and then reverse about 7 feet (2 m).

Once system checks are complete, Curiosity will set off for an area designated “Glenelg”, about 1,300 feet (400 m) southeast of the landing site. This was chosen because Glenelg is the intersection of three kinds of terrain with layered bedrock that makes a very good place to begin drilling operations to study the Martian geography.

"We're about ready to load our new destination into our GPS and head out onto the open road," says Curiosity Project Scientist John Grotzinger of the California Institute of Technology. "Our challenge is there is no GPS on Mars, so we have a roomful of rover-driver engineers providing our turn-by-turn navigation for us."

It’s a very tricky exercise made more difficult by the fact that Mars doesn’t have a magnetic field, so even a good old-fashioned compass isn’t available. But at least the Curiosity team can take comfort in having the first robot explorer with a genuine ray gun.